The project is designed to examine the structure with respect to interspersed repetitive DNA elements of protein encoding genes in mammalian cells. To do this cloned genomic DNA fragements contaniing mRNA coding sequences will be studied with the intent of examining their positional relationship to the major (only?) interspersed repetitive DNA element - known as the Alu family of interspersed repeated DNA. Further experiments will elucidate the interaction of two to three discrete RNA molecules that have been found to interact with these repetitive DNA elements.